The race to fill President Barack Obama’s old Senate seat has all the ingredients of a soap opera, with deep-seated rivalries, half-baked conspiracies and an ongoing criminal probe.

The only thing it lacks is romance — and actual candidates.

Politicians throughout Illinois have flirted with the idea of making a run for the seat, but most are still waiting to commit.

The current officeholder, Democratic Sen. Roland Burris, is almost certain to bow out, according to people familiar with his thinking.

State Treasurer Alexi Giannoulias, a Democrat and long-standing “friend of the president,” can only look on as national Democrats — including some in the White House — encourage Illinois Attorney General Lisa Madigan to abandon her potential plans for the governor’s mansion and make a run for the Senate instead.

Republican Rep. Mark Kirk looks like he’ll run for whatever post Madigan doesn’t — or opt to stay in the House. But nobody knows for sure what Madigan will do, and that’s got a lot of candidates on hold.

“Last time I talked to her, it was clear to me that she was leaning toward the governor’s race,” said Democratic Rep. Jan Schakowsky, who will announce Monday whether she’s running for the seat.

All things being equal, Schakowsky would prefer Madigan to stay focused on the statehouse.

“I see the potential of a weak field,” Schakowsky said of a primary without Madigan. “That’s a plus.”

Illinois Democrats have a history of eating their own, fumbling obvious opportunities as infighting creates a stalemate. The scandal surrounding indicted former Gov. Rod Blagojevich also creates an opening for the GOP. But the Republican Party in the Land of Lincoln remains a mess after a series of missteps, indictments and an Alan Keyes Senate bid in 2004.

Senate Republicans would like to see Kirk run, and they’re pushing him hard to do so. They’ve even warned him he could be redistricted out of his House seat when Democrats redraw the districts after the 2010 census. But he’s still uncommitted, saying only, “I’ve been thinking about running for reelection, for governor and for the Senate. Given the resources it takes to run a statewide race, I’ve been raising money.”

Given that waffling, Texas Sen. John Cornyn, the chairman of the National Republican Senatorial Committee, is reaching out to other potential candidates, including state party chairman Andy McKenna and Steve Preston, who served as the secretary of Housing and Urban Development in the final year of George W. Bush’s presidency.

“We’re not limiting our discussions with any single person,” Cornyn told POLITICO this week. “Until somebody steps up, it’s an open field.”

Blagojevich’s appointment of Burris created its own long-running drama, and it’s one that shows no signs of ending soon. Having told an Illinois state impeachment panel less than everything about his contacts with Blagojevich and his associates, Burris is now under investigation by both the Senate Ethics Committee and a local Illinois prosecutor.

Sources familiar with Burris’ thinking say it’s a near certainty he won’t run to keep his seat and will most likely make the announcement official by month’s end. But some of his allies see recent reports of White House interest in Madigan as an attempt to push him out — and warn that he might not respond kindly to them.

“They keep trotting out these marquee names to scare Roland,” said Delmarie Cobb, the senator’s media and political adviser, adding that some Democrats are out to “lynch” Burris and turn him into a “whipping boy.”

For his part, Burris said, “Everybody can run.”

In the end, Burris could amount to a supporting player in this revolving drama, but his appointment has created headache after headache for the senior senator from Illinois: Democrat Dick Durbin.

Durbin, a friend of Giannoulias, now says his mind is open when it comes to 2010 — just not where Burris is concerned.

“I’m talking to virtually all of the candidates and telling them what I think the lay of the land is,” Durbin said, naming Giannoulias, Madigan, Schakowsky and Chris Kennedy, the son of Robert Kennedy who operates the family’s massive Merchandise Mart in downtown Chicago.

Durbin has had a difficult relationship at times with Madigan’s father, Michael Madigan, the speaker of the Illinois statehouse and the chairman of the state’s Democratic Party, according to Democrats in Illinois and Washington. The elder Madigan, who is one of the most powerful political figures in a state with plenty of local heavyweights, has directed money from the party’s campaign coffers to statehouse campaigns over congressional races, much to the chagrin of Durbin and others.

In 2006, Durbin was strongly behind Tammy Duckworth — an amputee and an Iraq war veteran — in the midterm elections for a House seat in the Chicago suburbs. The state Republican Party flooded the district with mail in the final months of the campaign, and the state Democratic Party didn’t send a single piece of mail. Republican Rep. Peter Roskam won with a narrow 2 percent margin.

“We have our differences, but that’s not a surprise,” Durbin said, who added that he works “very well” with the state speaker and respects him “very much.”

Losing Obama’s seat in his first midterm election would be a black eye for the White House. White House chief of staff Rahm Emanuel and Obama strategist David Axelrod have told Giannoulias associates privately that their courtship of Madigan has less do with the treasurer’s weaknesses than it has to do with Madigan’s strengths as a statewide candidate. But Democratic sources say the White House is pushing hard for Madigan to run for the Senate, not the governor’s mansion.

“My political decision — our campaign’s decision — will have zero to do with what other people are doing or not doing,” the 33-year-old Giannoulias said about the prospects of a Madigan run.

Giannoulias says he hasn’t asked for an endorsement from Durbin, whom he calls a “great friend,” “the finest senator in the country” and someone with whom he often consults for political advice.

“I think at the end of the day, the DSCC and the White House want someone who will come out of the primary strong, come out of the general [and] be a good senator,” Giannoulias said.

Giannoulias, who raised a staggering $1.1 million in just 28 days after launching his campaign, has suffered some bad headlines recently for buying a hybrid with money from a state college fund that has lost more than $80 million in the past year. The treasurer said it was a legitimate expense. He also dismissed a whisper campaign — recycled from his first statewide race — suggesting that his family owns a “mob bank,” saying the attacks are made-up and unfair. His advisers are confident he can overcome this next round of negative attacks because he survived them once before.

Madigan’s candidacy could be wishful thinking by the White House. She has young kids in Illinois, and she couldn’t use the more than $4 million in campaign cash she’s already raised in her state account. Perhaps more important, her father clearly favors a run for governor.

In the absence of a clear-cut favorite, Illinois Democrats don’t expect the White House to weigh in with a heavier hand as the uncertainty persists.

“I’m really not surprised,” Schakowsky said. “The White House has a lot of friends back in Illinois.”